Behavioral performance of
wild-caught and laboratory-reared red drum Sciaenops ocellatus
(Linnaeus) larvae
M.E. Smith, L.A. Fuiman-2004
Journal of Experimental Marine Biology and Ecology, 302(1): 17-33
Abstract:
Laboratory- and hatchery-reared fish often differ
morphologically, physiologically, and/or behaviorally from wild-caught fish.
We compared the behavioral performance of laboratory-reared red drum (Sciaenops
ocellatus) larvae to that of wild-caught larvae to examine potential
differences due to rearing and to validate interpretations of experiments on
lab-reared larvae. Routine swimming speed and the timing and magnitude of
startle responses elicited by acoustic and visual stimuli were measured on
three size classes (developmental stages) of larvae (8, 13, and 27 mm TL).
Mean routine swimming speeds were greater in wild larvae compared to reared
larvae at 8 mm TL, but 27-mm wild larvae exhibited lower speeds than reared
larvae at 27 mm TL. In acoustically mediated startle responses, wild larvae
of all sizes were more responsive, took less time to respond, and in the
8-mm size class, had greater response distances and speeds than reared
larvae. In visually mediated startle responses, 8- and 13-mm reared larvae
had greater response distances and durations, while 27-mm wild larvae were
less responsive than reared larvae. These observations suggest caution when
inferring behavioral capabilities of wild larvae based on observations of
lab-reared red drum and that behavioral deficiencies due to rearing may
reduce survivorship of lab-reared red drum upon release into the
environment.
(Marine Science Institute, University of Texas at
Austin, 750 Channel View Dr., Port Aransas, TX 78373, USA, e-mail: mesmith@umd.edu)